Improvement in concrete pavements



106. COMPOSITIONS, COMING 0R PLASTIC. 8 6 6*@01/ 98 Cross Rererenc@ 0% J. e. STAFFORD 2. J. w. PHILLIPS.

CQNCRETE PAVEMENT.. No.187,926. Patented Fen.z'z.,1e77.

UNITED STATES PATENT OFFICE.

JOHN G. STAFFORD AND JAMES W. PHILLIPS, OF WASHINGTON, D. O.'

lMlROVEMENT IN CONCRETE PAVEMENTS.

Specification forming part of Letters Patent No. l 87,926, dated February 27, 1877; application filed January 19, 1877.

To all whom it may concern:

Be it known that we, JOHN G. STAFFORD and JAMES W. PHILLIPS, of Washington, in the`county of Washington and District ot' -Oolumbia, have invented a certain new and useful Improvement in Concrete Pavement, of which the following isa spectication, ret'- erence being had to the accompanying'drawing, which is a vertical section of our improved pavement.

The improved pavement consists, essentially, of a foundation of slabs and broken stone thoroughly bedded and packed. A base-course of broken stone, mixed with chemically-prepared bitumen, a binder-course of broken stone, heated and mixed with chemically-prepared bitumen, and a top or surface coat, consisting of clean sand, gravel, hydraulic cement, and a bituminous compound.

The invention further consists in the compositionof asphalt coal-tar, boiled at a high temperature, oil, oxide of iron, and brimstone, mixed with clean sand, gravel, and hydraulic cement, to form a top or surface coat of an asphalt or concrete pavement, as hereinafter described.

In carrying out our invention, we proceed as follows to lay'a ten to fteen inch pavement:

Foundation.

draulic or bituminous concrete, as preferred..

' Baraccano..

Third course: Any hard broken stone, from two to four inches in diameter, mixed with chemically-prepared bitumen, is spread evenly to the proper depth to suit the depth ot' pavement required, and thoroughly rolled with a steam-roller, or rammed with a steamlimestone or blue stone thirty pa y earth or white cla Eve parts; line hard cement ii E E l sand thirty parts; and Peekskill g avelz screened of the broken Astone into the interstices of the Y Binder-course.

Fourth course: Broken stone, from onehalf to one and one-half inches in diameter, free from dust, is heated to a little more than blood-heat, and then thoroughly mixed with chemically prepared bitumen, or coal tar boiled or distilled at a heat of 300, to which chemically-prepared bitumen, ten per cent. of the bitumen as prepared for the top coat, is added. It is then spread evenly over the street, and rolled and cross-rolled with a steam and stone roller to work the stone in place, and to consolidate the binder and base course.

Top or surface coat. i

Fifth course: A compound of ulverized rts; fullePs ve 1 r s; eau sharp angular through a half-inch screen, thlr y parts. After being' thoroughly mixed it is then heatedin rotary heaters; then mixed by suitabl'xf'hinery with the hereinafter-described bituminouscompound. It is then spread evenly over the binder-course, and rolled and cross-rolled first by hand, and then with steam and stone rollers, the composition being as follows: Three hundred and ninety-six pounds of' refined asphaltz two huded and follllr pounds of cliem ica y-prepare itumen t irty-six pouu s o a-a-r rammer, to work the points or sharp cornersoughly mixed in suitable kettles at a'proper temperature, according to the season, this mixture being mixed with chemically-prepared bitumen, in the required proportions to suit the climate and travel.

wenty pounds oxide of iron, fifteen pounds ot' rolled brimsttlTa-t'fof asphalt, boiled colei-gag, @b oxideofjron, and brnnstone, mixe 1n aboutthrtions `etter'im,end applied, together with clean sand, gravel, and hydraulic cement, to form a surface-coat, substantially as herein described and specified.

JOHN Gr. STAFFORD. J.' W. PHILLIPS.

`Witnesses: OCTAVIUS KNIGHT, CHAs. J. GoooH. 

